Charles H. Spurgeon on Psalms 53:5

There were they in great fear, where no fear was. David sees the end of the ungodly, and the ultimate triumph of the spiritual seed. The rebellious march in fury against the gracious, but suddenly they are seized with a causeless panic. The once fearless boasters tremble like the leaves of the aspen, frightened at their own shadows. In this sentence and this verse, this Psalm differs much from the fourteenth. It is evidently expressive of a higher state of realisation in the poet, he emphasises the truth by stronger expressions. Without cause the wicked are alarmed. He who denies God is at bottom a coward, and in his infidelity he is like the boy in the churchyard who "whistles to keep his courage up." For God hath scattered the bones of him that encampeth against thee. When the wicked see the destruction of their fellows they may well quail. Mighty were the hosts which besieged Zion, but they were defeated, and their unburied carcasses proved the prowess of the God whose being they dared to deny. Thou hast put them to shame, because God hath despised them. God's people may well look with derision upon their enemies since they are the objects of divine contempt. They scoff at us, but we may with far greater reason laugh them to scorn, because the Lord our God considers them as less than nothing and vanity.